Compound or multiple-expansion engine.



A. STAPPEN.` v COMPOUND 0R MULTIPLE EXPANSION ENGINE.

APPLIOLTIOI FILED JULY 5, 1911.

Patented Dec. 12,1911

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UNITED srATEs gPATENT. oEErcE.

ALBERT STAPPEN, OF MNCHEN-GLADBACH, GERMANY.

COMPOUND 0R MULTIPLE-EXPANSION ENGINE.

Specification of Letters Patent.

Patented Dec. 12, 1911.

Application led J'uly 5, 1911. Serial No. 636,837.

reference marked thereon, which form a part of this specification.

This invention relates to compound or multiple expansion engines, andhas for its object to provide improved means for obtaining an eiectiveheating of the piston or receiver. This can be obtained in a very simplemanner by constructing the piston of known form as a receiver, if onlythe,

heated surface is kept sufciently large. This, however, is impossible inconnection with the usual piston arrangement, as only the circularbottom of the piston is in contact with the steam.

My invention consists in constructing the piston as a plunger-like,stepped compound piston in which the high pressure steam, or generallyspeaking, the steam of the preceding cylinder, flows around thecylindrical surface of the piston. The heating surface obtained in thismanner is so large that the greatest reduction in condensation by thecylinder is obtained, which is necessary to get the minimum consumptionof steam and fuel.

Safety of working of the present enginel is absolutely maintained onaccount of the very simple construction, while in connection withreceivers, which are arranged.

In the accompanying drawing Figures 1 to 4 are longitudinal sections ofa cylinder and invention.

from the high pressure chamber.

piston of a compound engine embodying my Fig. 1 shows the piston in itsfirst dead point, admission taking place in the high pressure chamber,the low pressure chamber exhausting. Fig. 2 shows the high pressurechamber exhausting into the piston and compression taking place in thelow pressure chamber. Fig. 3 shows the piston in its second dead point,the high pressure chamber exhausted and admission taking place in thelow pressure chamber, and Fig. 4 shows compression in the high pressurechamber and exhaust from the low pressure chamber.

In said drawing a designates the inlet valve which controls the feedpipe (not shown) that enters the cylinder l; at one end of the highpressure chamber. The cylinder b is stepped, forming-two compartments ofdifferent diameters and an interior annular abutment b which constitutesone end wall of the high pressure chamber o2.

Reciprocably mounted within the cylinder o is a piston c which isstepped on its exterior to conform to the exterior of the cylinder andhas an annular exterior abut- `ment c which constitutes the other endwall of the high pressure chamber b2. The sides of the latter are formedby the portion of the cylinder having the largest diameter and by theportion of the piston having the vbetween the low pressure cylinder andthe interior of the piston is controlled by a valve f arranged tocontrol a port in-said wall o3 of the piston. This valve f ismechanically operated, by any suitable means, to admit steam to the lowpressure chamber from the piston which acts as a receiver for steam Thesteam is exhausted from the low pressure chamber through ports g in theperiphery of the latter when the piston has reached the limit of itsbackward stroke. The inlet for the steam may be constructed in anysuitable manner, for instance as a disk or drop valve, as shown. Theoperation of the valve f of the receiver is effected in a mannerdepending upon the constructional conditions of the engine.

Steam entering through the inlet into the high pressure chamber b2 actsupon the annular surface o and drives the piston toward the end b3 ofthe cylinder. As soon as the piston passes the point shown in Fig. 2steam from the high pressure chamber enters the piston through the portsd, the annular abutment b operating to distribute the steam. When thepiston reaches the position shown in F ig. 3 the steam in the highpressure chamber b2 has exhausted into the piston and by opening thevalve f the steam heated by the wall of the cylinder, enters the lowpressure chamber and reverses the stroke of the piston, and when thelatter reaches the position shown in Fig. 4 the steam begins to escapethrough the ports g.

I claiml. A compound engine comprising a hollow stepped piston havingexhaust ports at one end, a similarly stepped cylinder controlling saidports and having exhaust port-s controlled by the piston and means tocontrol the passage of low-pressure steam from the piston to thecylinder.

2. A compound steam engine, comprising a hollow piston having diametersof dii'erent size, a cylinder the diameters of which conform to thediameters of the piston, an admission valve at the high pressure part ofthe cylinder, said piston having peripheral ports in its small endportion, an admission v alve in the end of the large portion of saidpiston, said cylinder having exhaust ports in the low pressure portionthereof.

3. A compound steam engine comprising a cylinder -formed withcompartments of different diameters and an interior annular abutment atone end of the largest compartment, a hollow piston having its exteriorconforming to the cylinder, said cylinder and piston forming a highpressure chamber between their sides and a low pressure chamber betweentheir ends, an admission valve at the compression end of the highpressure chamber, said piston having peripheral ports in its small endportion, an admission valve in the end of the large portion of thepiston, said cylinder having exhaust ports in the low pressure chamber.

In testimony that I claim the foregoing as my invention, I have signedmy name in presence of two subscribing witnesses.

ALBERT STAPPEN. [Ls] Witnesses:

ALFRED I-IENKEL, ALBERT F. NUFER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

